Etherscan Plugin Improvement and fixes

[Aniket-Engg]

As per current status:

• Nothing happens on clicking icons if no API key provided. Actually that is a feature but user has no idea what to do next.
• After providing API key, clicking on Save, no message appears.
• No check on API key length

Home Tab:

• Form validation improvement, unnecessary cross icon
• Show constructor arguments field conditionally if required
• Show error in red.
• Show selected network in the plugin itself in read-only text

Receipts:

• Requests seems to pending in queue forever

Settings:

• Show API key in dots

[yann300]

• Unable to verify contracts which has openzeppelin imports.
• Unable to verify contracts that uses proxy.

[Aniket-Engg]

Suggestions from @LianaHus

• Make Generate Verification Scripts button secondary
• Add padding throughout the plugin UI
• Disable Verify Contract button when not all fields are provided

[LianaHus]

• titles
• font awsome icons instead of svg's

[Aniket-Engg]

• Add a user-friendly way for encoded constructor arguments